Frame structure for internal combustion engines with opposed pistons and a single crankshaft



July 23, 1957 J. E. JOHANSSON 2,800,271

FRAME STRUCTURE FOR INTERNAL. comsusnou ENGINES WITH OPPOSED PISTONS AND A SINGLE CRANKSHAFT Filed Feb. 4, 1954 IN VEN TOR.

mu wpvim United States Patent 'O Johan Erik Johansson, Gothenburg, Sweden, assignor to Aktiebolaget Gotavcrken, Gothenburg, Sweden, a corporation .of Sweden Application February 4, 1954, Serial No. 408,088

4 Claims. (Cl. 230-56) In connection with internal combustion engines with opposed pistons, it has previously beensuggested that the frame should be designed in such a way, that standards placed between the separate cylinders are connected with longitudinal trough-shaped beams, which form parts of the housings for the crank mechanism of the engine. If the engine is equipped with only one crank shaft, the upper piston is connected to this crank shaft by means of a yoke and two connecting rods. In order to provide a protected place for these rods and to reduce the length of the frame it is suggested, according to the present invention, to design the standards designed as hollow posts, inside of which the connecting rods are enclosed. In the case of two adjacent cylinders the front connecting rod of one piston and the rear connecting rod of the other are connected in the same space.

In the attached drawings the invention is illustrated by an example as applied to a three cylinder engine intended for use as a so called power gas generator. Fig. 1 is a diagrammatical perspective view of the frame structure, and Fig. 2 shows a detail of a longitudinal section of the intermediate cylinder and parts of the adjacent ones.

The frame comprises two central box shaped posts 1 and two also box shaped end posts 2, which in the longitudinal direction of the engine are connected to each other by two trough-shaped beams 3 and 4 which constitute parts of the housings for the crank mechanism of the engine. The lower beam rests upon and is connected to a bearing frame 5, which together with the lower beam constitutes the crank housing. The upper beam encloses the upper parts of the lateral connecting rods and also constitute the housing for the cylinders of a scavenging air compressor driven by the engine.

The engine cylinders are designed as separate units and are placed in the frame in such a manner that each cylinder can be easily inserted in and extracted from the frame, independently of the other cylinders. When being inserted, each cylinder is first moved in a slanting direction into the opening 6 in one of the beams, for instance the lower one, and is then swung into the frame and up through the opening 7 in the opposite beam. This opening is an exact fit for the corresponding part of the cylinder, and a loose liner 8 is fitted into the lower opening. The cylinder is finally bolted to a fastening device 9 near the centre of the post.

Each cylinder is provided with two pistons, a lower one 10, which through a connecting rod 11 is connected to the crank shaft 17, and an upper one 13 which through a yoke 14 and two lateral connecting rods 15 is also directly connected to the crank shaft 12. This shaft is mounted by separate portions 16 between adjacent cylinders. The crank pins for the lateral connecting rods are fastened to the portions 16. The crank pin for the main connecting rod 11 is carried by crank arms common to both kinds of connecting rods.

The lateral connecting rods are movable in the spaces formed inside the posts. The central posts will thus contain two connecting rods each, and must therefore be ice wider than the end posts which only contain one connecting rod each. The cylinder units are suitably placed in open spaces between the posts inside of which a protected place is afforded the movable rods. Further, a reduction in length of the engine is rendered possible. The side walls of the posts may be provided with suitably covered openings 17, through which the inside of the posts can be made accessible for mounting and inspecting the crank mechanism. V

In each cylinder, the upper piston is built together with a piston 18 in a compressor cylinder 19. The engine illustrated is devised to work as a power gas generator in which substantially the whole engine output is ab-. sorbed by the air compressors, from which the exhaust gases under high pressure are conveyed to a turbine or other expansion engine. 1 V

The upper trough-shaped beam is so designed asto form a housing for the compressor cylinders. It is therefore closed on top by a horizontal cover 20, and suitably has at least one more parallel partition wall (21, Fig. 2), not shown in Fig. 1, in which openings 22 for the compressor cylinders are provided. The cylinders consist of open linings 23 which are closed on top by covers 24 provided with the necessary valves.

Between the horizontal walls suitable reinforcing means in the form of cross webs 25 may be placed. It is then essential, however, to leave the bottom part of the beam free, so thata passage 26 remains between the various cylinders. These cylinders are open downwards, and the air which when the compressor pistons are working, is set in motion by their lower sides, will not be forced down into the posts and the crank housing, but a constant equalization will take place from one cylinder to the other, within the upper beam.

The above shown and described arrangement is only to be considered as an embodiment of the invention, the details of which may vary in many ways within the scope of the invention. In engines with many cylinders, the frame may be constructed in parts of suitable size which can be built together to a unit. The shape of the cylinders and their connection with the frame form no part of the invention and may be designed arbitrarily in a manner known per se. In engines of ordinary type, the compressors, intended for delivery of scavenging air only, do not become as large as illustrated, and it is not necessary to attach a compressor cylinder to each engine cylinder. The transmission of power from the upper piston to the connecting rod may be arranged such that shorter lateral connecting rods at their upper ends run on guide rails arranged inside the posts, the upper piston being connected, in the usual manner, to the guide shoe by means of rigid bars.

What is claimed is:

1. An internal combustion engine comprising vertical cylinders with opposed pistons and a crank mechanism having a single crank shaft and two connecting rods between each upper piston and said crank shaft, a frame structure consisting of vertical hollow posts 10- cated'between the engine cylinders, said cylinders being removable units adapted to be connected with and carried by said posts, and an upper and a lower troughshaped longitudinal beam connected with the upper and lower ends, respectively, of said hollow posts and forming parts of housings for said crank mechanism, said posts enclosing one connecting rod of each of two adjacent cylinders.

2. An internal combustion engine as recited in claim 1, wherein said hollow posts are provided with covered openings affording access to the connecting rods enclosed therein.

3. An internal combustion engine comprising vertical cylinders with opposed pistons and a crank mechanism aying asin le c anlsahattan two connecting rods we ac up r i ton 22 5. ais1 digit attains structure consisting of vertical hollow posts located between the cylinders, said cylinders being removable units adap fl t e cgmepts wit and c r ie -b said nests, an ip axe f lea e l QP h1h P qn inldiaa 'vbeam Tn l with t e u n r an lowe earl epa t e y Q a i' h l Pe t and q ni Pa of ousin s p.. Said drank mfi n s s id, we en lq n Qu amnes i l H of a of tw ad ac nt y n rs and anai compressor driven bysaid engine and comprising :cylin- P s n tth FQWPIt- Pist ns b in onn ed to pistons of the enginesaid upper beam having horiz nt wa s a d a etac erti al W bs merv nneet n Sa a l 'a i b ia 1 qqmnres p w in ev 4- A t mal Q P -St Qn en in wmPr an wt cal yli d s th q pa le P 9 a a crank mecha m h y Single W91? ha 4d 1W c nne n L ris b w e h' l pra r p st n andsaid c ank ha t .21 me structure consisting of vertical hollow post s located be W99 he lin er and QY QS1E$PQiQEI QQYQb uni ,anypner and lever trszu hzahaped v a a tn ina been connected with the upper and lower ends, respectively, of said hollow posts and forming parts of housings for said crank mechanism, said posts enclosing one connecting rod of each of two adjacent cylinders, and an air compressor driven by said engine and comprising cylind t an st th compmssqr stq s be n can: ne 't t p stons of t e eng ne, sa d pper beam having horizontal walls and transverse vertical webs'interconnecting said walls and supporting said compressor cylincrs s d mp es o y nd s being r pen d W a toward the lower'nd of said upper beam, said iipper beam having passages for the flow of air between the lower ends of the respective compressor-cylinders.

References Cited in the file of this patent UNITED STATES PATENTS n a er -fi --v--- Ma 6, 2 

